The overall purpose of the Biostatistics and Database Management Core is to provide biostatistical, epidemiological, and methodological consulting services and support, and central database management for the Program on Stress, the HPA and Health in Aging. The data collected in each Stanford project are stored in a single location in identified databases. All collaborating investigator scan access data and obtain analytic support via the Biostatistics Core. The staff of the Biostatistics Core perform data management tasks (such as error and correction), archive datasets datasets, and help carry out statistical. The latter function is especially important when analyses are complete and when data come from statistical analyses. The latter function is especially important when analyses are completely and when data come from several sources. This interactive data management and analysis is a key goal of the Program: to identify commonalities across studies by utilizing common measures, hypotheses, and analyses across studies. The design, development, and maintenance of the Program on Stress, the HPA and Health in Aging data hardware and software systems is the responsibility of the Biostatistics and Database Management Core. This Core will also assure quality control, confidentiality, and physical security of all Program on Stress, and the HPA and Health in Aging datasets. Professor Helena Kraemer will be available to the PI and all investigators for consultation on statistical issues. The data manager will have monthly contact via email or telephone with project investigators on high/her designate on each affiliated project to review issues of confidentiality of data, error detection methodology, and other data management issues. This Core also provides consultation on research efforts on both Core and Associates Investigators and develops methodology specific to the types of research projects supported by the Program on Stress, the HPA and Health in Aging.